For decades, in this and in foreign countries, virtually countless numbers of documents have been stored in media such as microfilm and microfiche. As an example, in the case of US census data, hundreds of millions of alphanumeric characters have been stored, in Hollerith code, in punch cards, or aperture cards. In general, these information storage techniques have represented cost-effective and convenient processes for archivng and distributing information.
As a result, storage of information on microfiche became widely popular and utilized by many organizations. Presently, one can find valuable and useful information stored on microfiche, for example, in commercial enterprises, law enforcement organizations and universities. It has been estimated that the number of documents stored on microfiche in the insurance industry alone is counted in the trillions. While the value of information stored on microfiche is recognized, recovering information from storage and rendering it usable by modern microfiche processing apparatus are frequently arduous, time consuming and labor intensive tasks.
Image scanners are often used for scanning and converting microfiche images into digital format However, conventional systems for accomplishing these task are complex and evasive. In this regard, reference may be made to U.S. pat. No. 5,845,018 titled "Method and Apparatus for Transferring Multiple Scanned Images from a First Medium to a Second Medium". While the invention therein disclosed has some utility and, indeed, attempts to simplify microfiche to digital document conversion, the apparatus itself is cumbersome and expensive. Further, operation of the apparatus is expensive since as many as one in every eight bits of high resolution data is supplied to a quality assurance station where a trained user determines if re-scanning is necessary. Clearly, it is desirable to have a relatively inexpensive microfiche processing apparatus that can be operated efficiently, without requiring skied employees to supervise system operations.
The situation is complicated further by the nature of typical microfiche media in which nonuniform images may be cropped, overlapped, skewed or distorted. They may have ragged or unclear borders. In such cases, conventional scanners have difficulty in locating the image to be scanned or determining the boundaries or edges of the image, especially in cases where the image is skewed For example, a conventional scanner may interpret a scratch on the microfiche as an image edge or boundary. Of course, such errors limit unattended operation of the scanner and when automatic scanner function fails, operator supervision and control become necessary, with concomitant increases in operating costs.
In view of the foregoing, it is clear that a need exists for a microfiche processing apparatus and method that produce superior digitized images from microfiche documents at high speeds and at substantially lower cost in comparison with conventional techniques. Desirably, such a system would itself be low in cost and capable of efficient, effective and unattended operation.